active acute adroit alacritous alert alive attentive awake breakneck bright brisk catty dashing deft dexterous dextrous dispatchful double-quick eagle-winged expeditious express fast featly fleet flying galloping graceful hair-trigger hasty headlong hustling keen light light of heel light-footed limber lissome lithe lively mercurial neat-fingered neat-handed nimble nimble-footed on the on the alert on the ball on the job peart precipitate prompt qui vive quick quick as lightning quick as thought rapid ready reckless resourceful running sharp sleepless smart snappy spanking speedy sprightly spry supple sure-footed swift tripping unblinking unnodding unsleeping unwinking volant wakeful wide-awake winged zippy